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141.
Geastrum berkeleyi, G. fornicatum, and G. minimum are newly recorded from Japan. A peristome of G. fornicatum has hitherto been described as indistinct, whereas the Japanese specimens have a well-delimited, fibrillose peristome. Geastrum minus, reported for the first time from Japan by Sanshi Imai, represents G. quadrifidum. Macroscopic and microscopic features of those four taxa are described and illustrated based on Japanese specimens.  相似文献   
142.
This fourth paper in the series considers five species of Inocybe occurring in Hokkaido, Honshu, and Kyushu. (1) Inocybe furfurea (section Tardae) is recorded from Hokkaido as new to Japan. (2) Inocybe luteola sp. nov. (section Tardae) is described from eastern Honshu (Chiba). It has smooth basidiospores and thick-walled caulocystidia descending to the middle of the stipe. (3) Inocybe napiformis sp. nov. [section Inocybe (= Cortinatae)], known from Hokkaido, appears close to Inocybe napipes, but characters of the metuloids distinguish the two species. (4) Inocybe grammata (section Marginatae) is recorded from Hokkaido and Nagano as new to Japan. (5) Inocybe pyriformis sp. nov. (section Marginatae) is described from Kyushu (Miyazaki). It has nodulose basidiospores and caulocystidia wholly covering the stipe surface. However, I. pyriformis is not typical in the section, lacking a marginate bulbous base in its stipe.  相似文献   
143.
144.
Capsaicinol is an ingredient of hot red pepper. In this study, we developed a novel method for capsaicinol synthesis and examined capsaicinol's physiological effects on capsaicin receptor (TRPV1)-related actions. Allylic oxidation of capsaicin by palladium acetate (Pd(OAc)(2)) resulted in the formation of (+/-)-capsaicinol acetate at a 7.2% yield in a single step. The effectiveness of (+/-)-capsaicinol in TRPV1 activation (EC(50)=1.1 microM) was found to be weaker than that of capsaicin (EC(50)=0.017 microM), whereas the efficacy of (+/-)-capsaicinol reached 75% of that of capsaicin. Intravenous administration of (+/-)-capsaicinol in anesthetized rats dose-dependently enhanced adrenaline secretion from the adrenal gland. The response to a 5 mg/kg-dose of (+/-)-capsaicinol was comparable to that of a 0.05 mg/kg-dose of capsaicin. The relative pungency of capsaicinol to capsaicin was coincident with the relative effectiveness in inducing these TRPV1-related actions.  相似文献   
145.
146.
Ascidian embryos sequester a specific cytoplasm, called the postplasm, at the posterior pole, where many maternal RNAs and proteins accumulate. Although the postplasm is thought to act as the germ plasm, it is also highly enriched in several factors essential for somatic cell development, and how the postplasm components regulate both germ and somatic cell differentiation remains elusive. Using a vasa homolog, CiVH, and other postplasmic components as markers, we found that the postplasm-containing blastomeres, the B7.6 cells, undergo an asymmetric cell division during gastrulation to produce two distinct daughter cells: B8.11 and B8.12. Most of the postplasmic components segregate only into the B8.11 cells, which never coalesce into the gonad. By contrast, the maternal CiVH RNA and protein are specifically distributed into the B8.12 cells, which divide further and are incorporated into the gonad in juveniles. In the B8.12 cells, CiVH production is upregulated from the maternal RNA source, resulting in the formation of perinuclear CiVH granules, which may be the nuage, a hallmark of germ cells in many animal species. We propose that the redistribution of specific maternal molecules into the B8.12 cells is essential for germ-cell specification in ascidians.  相似文献   
147.
Ceriporiopsis subvermispora is a selective white-rot fungus that secretes alk(en)ylitaconic acids named ceriporic acids, known as ion redox silencers. In this study, we analysed a series of extracellular lipid-related metabolites produced by the fungus and found that a wide variety of ceriporic acids and fatty acids, including those with odd-numbered and very long-chains, were produced in wood meal cultures. Two new ceriporic acids, (R)-3-[(Z)-tetradec-7-enyl]-itaconic acid (ceriporic acid E) and (R)-3-[(Z)-tetradec-5-enyl]-itaconic acid (ceriporic acid F), were for the first time identified by dimethyl disulfide derivatisation, followed by GC/EI-MS, (1)H and homonuclear J-resolved 2D NMR and feeding experiments with [(13)C-U] glucose coupled with multiple-stage mass spectrometry. In separation by GC and LC, a reversed correlation of elution sequences between a nonpolar GC column and an ODS-LC column for cis and trans isomers of ω7 and ω9 lipids was found, and the elution of new metabolites was in accordance with the prevailing theory. The biosynthetic precursors of ceriporic acid F can be proposed as oxaloacetate and 16:1Δ7-CoA. Because fatty acids biosynthesised from 16:1Δ7-CoA have been reported for only a limited number of organisms, the highly individual structure of ceriporic acid F is highlighted.  相似文献   
148.

Background

Influenza A virus can infect a variety of different hosts and therefore has to adapt to different host temperatures for its efficient viral replication. Influenza virus codes for an RNA polymerase of 3 subunits: PB1, PB2 and PA. It is well known that the PB2 subunit is involved in temperature sensitivity, such as cold adaptation. On the other hand the role of the PA subunit in thermal sensitivity is still poorly understood.

Methodology/Principal Findings

To test which polymerase subunit(s) were involved in thermal stress we reconstituted artificial hybrids of influenza RNA polymerase in ribonucleoprotein (RNP) complexes and measured steady-state levels of mRNA, cRNA and vRNA at different temperatures. The PA subunit was involved in modulating RNP activity under thermal stress. Residue 114 of the PA subunit was an important determinant of this activity.

Conclusions/Significance

These findings suggested that influenza A virus may acquire an RNA polymerase adapted to different body temperatures of the host by reassortment of the RNA polymerase genes.  相似文献   
149.
Developmental dynamics of neural stem/progenitor cells (NSPCs) are crucial for embryonic and adult neurogenesis, but its regulatory factors are not fully understood. By differential subtractive screening with NSPCs versus their differentiated progenies, we identified the radmis (radial fiber and mitotic spindle)/ckap2l gene, a novel microtubule-associated protein (MAP) enriched in NSPCs. Radmis is a putative substrate for the E3-ubiquitin ligase, anaphase promoting complex/cyclosome (APC/C), and is degraded via the KEN box. Radmis was highly expressed in regions of active neurogenesis throughout life, and its distribution was dynamically regulated during NSPC division. In embryonic and perinatal brains, radmis localized to bipolar mitotic spindles and radial fibers (basal processes) of dividing NSPCs. As central nervous system development proceeded, radmis expression was lost in most brain regions, except for several neurogenic regions. In adult brain, radmis expression persisted in the mitotic spindles of both slowly-dividing stem cells and rapid amplifying progenitors. Overexpression of radmis in vitro induced hyper-stabilization of microtubules, severe defects in mitotic spindle formation, and mitotic arrest. In vivo gain-of-function using in utero electroporation revealed that radmis directed a reduction in NSPC proliferation and a concomitant increase in cell cycle exit, causing a reduction in the Tbr2-positive basal progenitor population and shrinkage of the embryonic subventricular zone. Besides, radmis loss-of-function by shRNAs induced the multipolar mitotic spindle structure, accompanied with the catastrophe of chromosome segregation including the long chromosome bridge between two separating daughter nuclei. These findings uncover the indispensable role of radmis in mitotic spindle formation and cell-cycle progression of NSPCs.  相似文献   
150.
We designed and synthesized a series of 3-aryl-3-hydroxy-1-phenylpyrrolidine derivatives D and evaluated their potential as novel androgen receptor (AR) antagonists therapeutically effective against castration-resistant prostate cancer (CRPC). Introduction of a methyl group at the 2-position (R2) of the pyrrolidine ring increased the AR binding affinity. The (2S,3R) configuration of the pyrrolidine ring was favorable for the AR antagonistic activity. It was found that introduction of an amide substituent (R1) and a pyridin-3-yl group (Q) was effective for reducing the AR agonistic activity which appeared during the optimization of lead compound 6. Compound 54 showed potent antitumor effects against a CRPC model of LNCaP-hr cell line in a mouse xenograft, in which bicalutamide exhibited only partial suppression of tumor growth. Thus, the pyrrolidine derivatives such as 54 are novel AR antagonists, and their properties having efficacy against CRPC are distinct from those of a representative first-generation antagonist, bicalutamide.  相似文献   
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